My story is similar. I also felt the burn out between March and September and decided to leave at the beginning of September. I felt like the work I do is boring, everyday standup meetings are annoying as well as planning, grooming meetings and all this things. After I left the company, I could not do anything productive for a few months, but now I am more productive. I am working on my pet projects, taking some time for walking and cooking, reading books, preparing for the interviews. Taking a few months off helped me at least feel much better.